This adaptation is called apical growth - the tip of each part of the plant is the only part which will continue to grow indefinitely. It leads to long, branching structures which are well adapted for collecting as much light as possible, maximising the opportunities for photosynthesis.

However, this does lead to a problem. Out on the land, in order to ‘fix’ carbon dioxide, you can’t just use the gas dissolved in the water. You aren’t in the water any more. You need to open parts of your photosynthesising structures to let the carbon dioxide in before it dissolves in your internal water, where you can use it. But this means that you will lose water to the air through evaporation.

So far, as a small plant, it’s been sufficient to allow water to migrate through you between your cells via a physical process called osmosis, in which water will migrate to the most concentrated part of the plant.

Unfortunately, osmosis is limited to fairly short distances and you have just got a lot longer thanks to your apical growth adaptation.

You could use some adaptation for carrying that water around… like… a tube?